website introduction：A crossword solving search engine with a reverse feature that lets you see other clues pointing to an answer.
website introduction：Primarily a dictionary site but also has the ability to do wildcard searches on the words it knows about.
website introduction：Collection of crossword solving tools and crossword thesaurus to help fill in the blanks in crossword puzzles.
website introduction：Nonstop fun with the world's best logic puzzles: free online picture-forming logic puzzles
website introduction：Simple web-based letter pattern searcher.
website introduction：Brain teasers, puzzles, riddles, games and optical illusions.
website introduction：Everything Rubik's related, forums, online cubes, games, contests and history.
website introduction：Search by clues, word lengths, or partial words with wildcards.
website introduction：Puzzles playable online, sizes 3x3 to 9x9, as well as tutorials and tips.
website introduction：Brain teasers, riddles, logic puzzles and problems, paradoxes, optical illusions, IQ tests and logical games.
website introduction：Play sudoku puzzles online for free.
website introduction：Use our free crossword puzzle solver. Crossword clues and answers gathered daily. Guaranteed to find any answers for any crossword puzzles.
website introduction：Contains a huge collection of user submitted and rated brain teasers and riddles. It also has a lively message board and some unique multiplayer games.
website introduction：killer sudoku and greater than sudoku puzzles from easy to very difficult. New puzzles every day. Play on-online or download for off-line play.
website introduction：Forum dedicated to speedsolving the Rubik's cube, asking questions, and cubers community.
website introduction：Official competitions, world records, top persons and stats by the official Cube association.
website introduction：Amusing daily blog which reviews the New York Times puzzle.
website introduction：This site contains logical puzzles. It contain puzzle types which appears in World Puzzles Championships. This site also contains Sudoku types which appears in World Sudoku Championships.
website introduction：Makes wire puzzles of various levels of difficulty.
website introduction：Online Rubik's Cube timer for speedcubing. Scrambling generator, allowing inspection, calculating averages and other stats.
website introduction：Daily killer and greater-than killer sudoku puzzles that can be played online or printed.
website introduction：The stress here is on relative novelty and interactivity, in combination with a scientific background. Regularly updated.
website introduction：Interactive java puzzles and activities in different mathematical topics.
website introduction：Site with Sudoku and many variants, as well solvers, strategy explanations, etc.
website introduction：Home site for the Binary Arts line of mind puzzles.